1. Field of the Invention
The present invention relates to a light emitting diode package; and more particularly, to a surface mounting type light emitting diode package having an excellent heat radiation characteristic.
2. Description of the Related Art
In general, a light emitting diode (hereinafter, referred to as ‘LED’) is an electronic component generates a minority of carriers (electrons or holes) injected by using a p-n junction structure of a semiconductor and emits light by the recombination of the carriers. That is, when the electrons and holes are recombined with each other with moving through a junction portion of an anode and a cathode at the time of applying a forward voltage to a semiconductor of a predetermined element, the energy of the recombined electrons and holes is smaller than energy generated when the electrons and the holes are separated from each other. Therefore, light is emitted by a difference in energy at this time.
Since such light emitting diode can emit high-efficiency light at a low voltage, the light emitting diode is used in a home electronic appliance, a remote controller, a signboard, a display, various automated machines, and the like.
In particular, various components of telecommunication apparatuses, such as a resistor, a condenser, a noise filter, and the like are further miniaturized with the miniaturization and slimness of telecommunication apparatuses. The light emitting diode is also fabricated in a surface mount device (hereinafter, referred to as ‘SMD’) type to be mounted directly on a light emitting diode PCB (Printed Circuit Board).
The SMD-type light emitting diode package is fabricated by a top view method and a side view method according to the usage of the SMD-type light emitting diode package. Recently, the SMD-type light emitting diode package is inactivated to heat due to the miniaturization and slimness.
Hereinafter, a conventional light emitting diode package will be described in detail with respect to FIG. 1.
FIG. 1 is a schematic view illustrating a structure of a conventional surface mounting-type LED package.
Referring to FIG. 1, the conventional lighting emitting diode package includes a lead frame 50 composed of a pair of lead terminals, a mold 10 made of a synthetic resin material to receive a part of the lead frame 50 in the inside thereof, an LED chip 30 mounted on the lead frame 50 positioned in the mold, an electrode connection unit 40 for electrically connecting the lead frame 50, and a molding agent 20 for protecting the LED chip 30 and the electrode connection unit 40.
An irradiation window opened to easily radiate light is formed on a predetermined surface of the mold 10 and the lead frame 50 composed of the pair of lead frames is formed on the other surface to be mounted on a printed circuit board (not shown). At this time, the lead frame 50 covers an outside, that is, parts of a side surface and a bottom surface of the mold 10.
Accordingly, the LED chip 30 is mounted on the lead frame 50 composed of the pair of lead terminals and thus most of heat discharged from the LED chip 30 is discharged through the lead frame 50 connected to the LED chip 30.
However, the conventional lead frame 50 is bent to cover the parts of the side surface and the bottom surface of the mold 10 through an additional bending process so as to be electrically connected to the printed circuit board to be mounted on a surface corresponding to the irradiation window of the mold 10, that is, the bottom surface of the mold 10.
However, when the lead frame covers the parts of the side surface and the bottom surface of the mold, an overall length of the lead frame is increased and thus heat conductivity is lowered, whereby the quantity of heat irradiatable through the lead frame also decreases.
When the quantity of the heat irradiatable through the lead frame decreases, the lead terminal mounted with the LED chips is overcome by the heat to be black colored or the bonding of a wire for electrically connecting the LED chips to the lead frame.
Accordingly, the characteristic and reliability of the light emitting diode package are lowered and light efficiency is also lowered due to the discoloration of the lead terminal.